Method and apparatus for increasing the density of tobacco in predetermined sections of a tobacco braid

ABSTRACT

In a cigarette making machine forming a continuous cigarette rod from a braid of cut tobacco, short sections or increments of cut tobacco are periodically added to and held by a pneumatic tape prior to the receipt by the pneumatic tape of the trimmed braid of cut tobacco from a pneumatic braid forming wheel. The increments of cut tobacco are added onto the tape in synchronism with the movement of the tape and the cigarette rod cut off device so that the center line of each of the increments coincides substantially with the line where the cigarette rod will be cut to form a single cigarette.

C ristiani [451 Mar. 5, 1974 METHOD AND APPARATUS FOR INCREASING THE DENSITY OF TOBACCO IN PREDETERMINED SECTIONS OF A TOBACCO BRAID [75] Inventor: Athos Cristiani, Bologna, Italy [73] Assignee: AMF Incorporated, White Plains,

[22] Filed: Sept. 11, 1972 [21] Appl. No.: 287,786

Related U.S. Application Data [63] Continuation of Ser. No. 91,999, Nov. 23, 1970,

abandoned.

[52] U.S. Cl .Q 131/84 C, 131/61 B [51] Int. Cl. A24c05/18 [58] Field of Search 131/61 R, 61 B, 76, 84, 88

[56] References Cited UNITED STATES PATENTS 3,306,305 2/1967 Molins 131/61 B 1,721,117 7/1929 Hopkins 131/61 B X 3,196,880 7/1965 Pinkham 131/61 B 1,977,998 10/1934 Podmorc 131/61 B FOREIGN PATENTS OR APPLICATIONS 948,736 2/1964 Great Britain 131/61 B 880,850 10/1961 Great Britain 131/84 (I 897,551 5/1962 Great Britain 982,382 2/1965 Great Britain 813,576 5/1959 Great Britain 1,105,322 4/1961 (Icrmany 131/84 Primary Examiner Joseph S. Reich Attorney, Agent, or Firm-George W. Price; Charles J. Worth 57 ABSTRACT In a cigarette making machine forming a continuous cigarette rod from a braid of cut tobacco, short sections or increments of cut tobacco are periodically added to and held by a pneumatic tape prior to the receipt by the pneumatic tape of the trimmed braid of cut tobacco from a pneumatic braid forming wheel. The increments of cut tobacco are added onto the tape in synchronism with the movement of the tape and the cigarette rod cut off. device so that the center line of each of the increments coincides substantially with the line where the cigarette rod will be cut to form a single cigarette.

6 Claims, 1 Drawing Figure ROTATION SYNCHRON/ZED 7'0 CUT OFF DEV/CE 3c TAPE 3 This application is a continuation of my copending application ser. No. 91,999, filed Nov. 23, 1970, now abandoned.

This invention relates generally to cigarette makers of the type which forms a continuous braid of cut to-' bacco that is subsequently wrapped longitudinally in a paper tape and then sealed as a tube to form a continuous cigarette rod, the rod then being cut at regular intervals into predetermined lengths to obtain individual cigarettes. More particularly, this invention relates to a method and apparatus for increasing the density of the cut tobacco braid where the rod is cut when making individual cigarettes and is an improvement over the method and apparatus for forming a tobacco rod of my U.S. application, Ser. No. 742,93l, now U.S. Pat. No. 3,548,837. I

Cigarettes have a tendency to shed or lose cut tobacco from their ends. Tobacco is most commonly lost from cigarette ends when the cigarettes are collected after the rod is cut, and during the subsequent processing of the cigarettes such as adding filter plug assemblies packing the cigarettes and, to a smaller degree, parcelling of the cigarettes. Loss of tobacco from the ends of cigarettes is also caused by repeated manipulations of the cigarette package by the smoker.

Currently, in cigarette making machines, as shown and described in U.S. Pat. No. 3,548,837, the core of cigarettes is formed by feeding cut tobacco which has been adequately disentangled to a movable support such as a pneumatic wheel. The cut tobacco is held on to the surface of the wheel by suction, assumes the shape of a rod, and is commonlyreferredto as a braid which is usually soft and continuous. To provide a braid that has desired dimensions, surplus tobacco is removed by a trimming device. The braid which has been trimmed to a uniform thickness is deliveredto a transfer unit, for instance, a pneumatic tape, for further processing. Subsequently, the braid is Wrappedin a paper tape which is sealed to become -a continuous cigarette rod that is then cut into predetermined equal lengths or segments where each length or segment constitutes a single cigarette. The movements of the multiple elements forming the cigarette rod are synchronized with the cigarette rod cutter so that all'the cigarettes obtained from the cigarette rod are cut to a desired equal same length. i

Thus, it is possible to' locate rather accurately the positions or lines on-the cigarette rod and moving braid where cuts will be made by the cutoff mechanism to form the individual cigarettes. In accordance'with this invention, short sections or increments of cut tobacco are periodically added to the: pneumatic tape prior to the receipt by the pneumatic tape of the trimmed braid of cut tobacco from the pneumatic wheel. The increments of cut tobacco are added onto the tape in synchronism with the movement of the tape and the rod cut off device so that the center line of each of the intape to combine with the periodically added and intermittently positioned incremental lengths of cut tobacco supported by the tape to provide a greater concentration of tobacco at the ends of the formed cigarettes.

If desired, the incremental lengths of cut tobacco can be formed from the surplus tobacco cut off or removed from the tobacco braid by the trimming device. In this manner, the excess tobacco can be re-utilized practically immediately after it is removed or trimmed from the braid and in the vicinity of the area where this excess or rejected tobacco is removed.

In accordance with this invention, incremental lengths of cut tobacco of predetermined dimensions formed from surplus or excess tobacco rejected or removed from the braid by the trimming device are transferred, at regular intervals, to a pneumatic tape upstream of the point where the trimmed braid is transferred onto the tape. The transfer of the incremental lengths of cut tobacco is synchronized with the tape movement and cut off knife movement in such a manner that the incremental lengths of cut tobacco transferred to the tape have their center lines in substantial alignment with the lines along which the cigarette rod is cut to form the single cigarettes.

Additionally, in accordance with this invention, the

incremental lengths of cut tobacco can be subjected to 4 a trimming action prior to being transferred to the tape to insure uniformity of size of the various incremental lengths. I I

The novel features of this invention are set forth in the appended claims. The invention itself, however,

crem'ents coincides substantially with a line where the will best be understood from the following description when read in connection with the accompanying drawings. Y

The single FIGURE of the drawings isa schematic side elevational view of a portion ofa cigarette making machine with parts thereof broken away to better illustrate the present invention. Referring now to the drawing, in accordance with this invention and, a suction wheel I is provided at its periphery anumber of slots 101, arranged circumferentially and equispaced angularly from each other. The bottom of each slot is open for selective coupling to a source of suction connected to the. interior chamber of wheel 1 by suitable means, not illustrated. A curved shutter 2 within wheel 1, selectively controls the coupling of the slots 10] 'to the source of suction by selectively blocking the opening at the bottom of each s1ot.'The shutter '2.extends along an arc of predetermined length as illustrated in the drawing.

Wheel 1 is operatively positioned between trimming device 6 (corresponding to trimming device 83 of U.S. Pat, No. 3,548,837) associated .with the pneumatic wheel 5 corresponding to wheel of U.S. Pat. No.

3,548,837) of a cigarette maker and an area of tape 3 corresponding to conveyor 88 of U.S. Pat. No. 3,548,837) upstream of the point where the braid is transferred from the wheel 5 due to termination of a vacuum or suction thereto to the tape 3 which is coupled to a vacuum or suction as shown. Wheel 1 receives and holds in its slots I01 at least-a part of the cut tobacco trimmed from the braid by the trimming device 6, thereby forming the incremental lengths of cut tobacco 9. A second trimming device such as of a pin roller 4 or the like preferably is provided to trim or remove the excess cut tobacco from the incremental lengths of cut tobacco 9, contained in slots 101. Normally, the quantity of tobacco removed by trimming device 6 is in excess of the amount of tobacco required for forming the incremental lengths of cut tobacco 9. The tobacco trimmed from the incremental lengths of cut tobacco 9 in the slots 101 together with the tobacco trimmed from the braid by trimming device 4 is conveyed to or collected on transfer tape 7 (corresponding to conveyor 85 of US. Pat. No. 3,548,837) which returns this tobacco to the hopper, not shown.

The incremental lengths of cut tobacco 9 are fed to the tape 3 at the point where the tape 3 and wheel 1 meet, and under the influence of suction or a vacuum acting through the tape 3 are picked up and held by the tape 3, the suction to the slots 101 when properly positioned adjacent the tape 3 having been cut off to permit the incremental lengths of cut tobacco to be transferred. Note, in the drawing, one end 102 of shutter 2 shuts off the suction slightly in advance of the slot 101 of wheel 1 contacting tape 3.

The speed of rotation of wheel 1 is synchronized to the rate of advance of tape 3 and the speed of the rod cut off device conventionally employed in cigarette making machines such that sequential incremental lengths of cut tobacco 9 transferred by the wheel 1 onto the tape 3 are equispaced from each other by a distance corresponding substantially to the length of a cigarette. As the incremental lengths of cut tobacco 9 on the tape 3 reach the point where the tape 3 is adjacent the wheel 5, the trimmed tobacco braid 8, delivered by the wheel to the tape, is held to the tape 3 by suction and covers the incremental lengths of cut tobacco 9 previously transferred to the tape 3 by the wheel 1. Thus, the rod formed on and supported by the tape 3 has equispaced sections of braid 9 having incremental lengthsof cut tobacco 9 in which the density of tobacco is greater than in the'other portions ofthe braid.

The timing of the rotation of wheel 1 relative to the rate of advance of tape 3 and the speed of the rod cut off device is such that the incremental lengths of cut tobacco occupy those portions of the rod where the cut is actually made to form single cigarettes. The resulting single cigarettes so obtained have a higher density of tobacco at their ends, to prevent or compensate for the subsequent loss of tobacco or end leakage effect which can occur during subsequent manipulations and handling of the cigarettes up to the actual smoking of the cigarette.

Obviously, many modifications and variations of the present invention are possible in the light of the above teaching. lt is, therefore, to be understood that the invention may be practiced otherwise than as specifically described herein.

What is claimed is:

1. Apparatus for increasing the density of portions of a stream of tobacco, which comprises:

a conveyor belt for receiving and conveying a stream of tobacco of predetermined thickness,

a cylindrical member mounted for rotation about an axis spaced from the eonveyorbelt a distance substantially equal to the radius of the cylindrical member and the predetermined thickness of the tobacco stream, the cylindrical member being operable to receive a stream of tobacco and convey it to said conveyor belt,

a wheel mounted for rotation about an axis spaced from the conveyor belt a distance substantially equal to the radius of the wheel, said axis being located upstream of the cylindrical member axis with respect to the conveyor belt,

means providing tobacco holding slots in the periphery of the wheel,

means for generating a suction force coupled to the slots in the wheel, means mounted adjacent the cylindrical member for trimming the tobacco held thereon to said predetermined thickness, the trimmed tobacco being conveyed to the slots in the wheel at least partially by the suction being generated thereat, and

means for transferring the tobacco increments from the slots to the conveyor belt upstream of the receipt thereon of the stream of tobacco from the cylindrical member, the tobacco increments being overlayed by the tobacco stream as the conveyor belt is driven and compacted therein by the cylindrical member.

2. Apparatus according to claim 1, wherein the slots are spaced apart on the wheel a distance approximately equal to the tobacco portion of a cigarette.

3. Apparatus according to claim 1, wherein suction means are coupled to the cylindrical member to hold the stream of tobacco thereon.

4. Apparatus according to claim 2, wherein suction means are coupled to the cylindrical member to hold the stream of tobacco thereon. a

5. Apparatus according to claim 1, wherein: the conveyor belt is coupled to a source of suction and the tobacco delivered thereto by the cylindrical member is held on the conveyor belt by suction, and

the tobacco increment transferring means includes means for successively placingthe slots in juxtaposition with the conveyor belt and means for interrupting the suction coupled to the slots in the wheel as the slots are placed in juxtaposition with the conveyor belt. v

6. Apparatus for increasing the density of portions of a stream of tobacco, which comprises:

a conveyor belt for receiving and conveying a stream of tobacco of predetermined thickness,

means for conveying a stream of tobaceoto the conveyor belt, at least a portion of the means being mounted adjacent to the conveyor belt, means for forming a succession of tobacco increments, said means being mounted adjacent the conveyor belt upstream of the tobacco stream conveying means, and including a wheel having means providing a series of slots therein, suction means coupled to said slots to retain the increments of to. bacco therein, means for supplying tobacco to-said slots, and means for rotating the wheel to drive the tobacco filled slots into juxtaposition with the conveyor belt,

said means for supplying tobacco to said slots including means mounted adjacent the tobacco stream conveying means for trimming the stream of tobacco thereon to a predetermined depth, the excess tobacco particles being directed toward the slots in the increment forming wheel by the inertia provided by the tobacco stream conveying means, and

means for transferring the tobacco increments from the tobacco increment forming means to the conveyor belt upstream of the receipt thereon of the stream of tobacco from the tobacco stream conveying means, the tobacco i'ncrements being overlayed by the tobacco stream as the conveyor belt is driven and compacted therein by said tobacco stream conveying means. 

1. Apparatus for increasing the density of portions of a stream of tobacco, which comprises: a conveyor belt for receiving and conveying a stream of tobacco of predetermined thickness, a cylindrical member mounted for rotation about an axis spaced from the conveyor belt a distance substantially equal to the radius of the cylindrical member and the predetermined thickness of the tobacco stream, the cylindrical member being operable to receive a stream of tobacco and convey it to said conveyor belt, a wheel mounted for rotation about an axis spaced from the conveyor belt a distance substantially equal to the radius of the wheel, said axis being located upstream of the cylindrical member axis with respect to the conveyor belt, means providing tobacco holding slots in the periphery of the wheel, means for generating a suction force coupled to the slots in the wheel, means mounted adjacent the cylindrical member for trimming the tobacco held thereon to said predetermined thickness, the trimmed tobacco being conveyed to the slots in the wheel at least partially by the suction being generated thereat, and means for transferring the tobacco incrementS from the slots to the conveyor belt upstream of the receipt thereon of the stream of tobacco from the cylindrical member, the tobacco increments being overlayed by the tobacco stream as the conveyor belt is driven and compacted therein by the cylindrical member.
 2. Apparatus according to claim 1, wherein the slots are spaced apart on the wheel a distance approximately equal to the tobacco portion of a cigarette.
 3. Apparatus according to claim 1, wherein suction means are coupled to the cylindrical member to hold the stream of tobacco thereon.
 4. Apparatus according to claim 2, wherein suction means are coupled to the cylindrical member to hold the stream of tobacco thereon.
 5. Apparatus according to claim 1, wherein: the conveyor belt is coupled to a source of suction and the tobacco delivered thereto by the cylindrical member is held on the conveyor belt by suction, and the tobacco increment transferring means includes means for successively placing the slots in juxtaposition with the conveyor belt and means for interrupting the suction coupled to the slots in the wheel as the slots are placed in juxtaposition with the conveyor belt.
 6. Apparatus for increasing the density of portions of a stream of tobacco, which comprises: a conveyor belt for receiving and conveying a stream of tobacco of predetermined thickness, means for conveying a stream of tobacco to the conveyor belt, at least a portion of the means being mounted adjacent to the conveyor belt, means for forming a succession of tobacco increments, said means being mounted adjacent the conveyor belt upstream of the tobacco stream conveying means, and including a wheel having means providing a series of slots therein, suction means coupled to said slots to retain the increments of tobacco therein, means for supplying tobacco to said slots, and means for rotating the wheel to drive the tobacco filled slots into juxtaposition with the conveyor belt, said means for supplying tobacco to said slots including means mounted adjacent the tobacco stream conveying means for trimming the stream of tobacco thereon to a predetermined depth, the excess tobacco particles being directed toward the slots in the increment forming wheel by the inertia provided by the tobacco stream conveying means, and means for transferring the tobacco increments from the tobacco increment forming means to the conveyor belt upstream of the receipt thereon of the stream of tobacco from the tobacco stream conveying means, the tobacco increments being overlayed by the tobacco stream as the conveyor belt is driven and compacted therein by said tobacco stream conveying means. 